1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
jeyben [28]
3 years ago
9

Raindrops fall vertically at 7.5 m/s relative to the Earth. What does an observer in a car moving at 20.2 m/s in a straight line

measure as the velocity of the raindrops? (Assume the car is moving to the right and that the +x-axis is to the right. Enter the magnitude in m/s and the direction in degrees counterclockwise from the +x-axis.)
Physics
1 answer:
Vilka [71]3 years ago
4 0

Answer:

vDP = 21.7454 m/s

θ = 200.3693°

Explanation:

Given

vDE = 7.5 m/s

vPE = 20.2 m/s

Required:  vDP

Assume that

vDE to be in direction of - j

vPE to be in direction of i

According to relative motion concept the velocity vDP is given by

vDP = vDE - vPE     (I)

Substitute in (I) to get that

vDP = - 7.5 j - 20.2 i

The magnitude of vDP is given by

vDP = √((- 7.5)²+(- 20.2)²) m/s =  21.7454 m/s

θ = Arctan (- 7.5/- 20.2) = 20.3693°

θ is in 3rd quadrant so add 180°

θ = 20.3693° + 180° = 200.3693°

You might be interested in
From a vantage point very close to the track at a stock car race, you hear the sound emitted by a moving car. You detect a frequ
Alexandra [31]

Approximately 15 m/s is the speed of the car.

<u>Explanation:</u>

<u>Given:</u>

speed of sound - 343 m/s

You detect a frequency that is 0.959 times as small as the frequency emitted by the car when it is stationary. So, it can be written as,

f^{\prime}=0.959 f

\frac{f^{\prime}}{f}=0.959

If there is relative movement between an observer and source, the frequency heard by an observer differs from the actual frequency of the source. This changed frequency is called the apparent frequency. This variation in frequency of sound wave due to motion is called the Doppler shift (Doppler effect). In general,

                     f^{\prime}=\left(\frac{v+v_{0}}{v-v_{s}}\right) \times f

Where,

f^' - Observed frequency

f – Actual frequency

v – Velocity of sound waves

v_0 – Velocity of observer

v_s - velocity of source

When source moves away from an observer at rest (v_{0} = 0), the equation would be

                        f^{\prime}=\left(\frac{v}{v-\left(-v_{s}\right)}\right) \times f

                        f^{\prime}=\left(\frac{v}{v+v_{s}}\right) \times f

                        \frac{f^{\prime}}{f}=\left(\frac{v}{v+v_{s}}\right)

By substituting the known values, we get

            0.959=\left(\frac{343}{343+v_{s}}\right)

           0.959\left(343+v_{s}\right)=343

           0.959(343)+0.959\left(v_{s}\right)=343

           328.937+0.959 v_{s}=343

           0.959 v_{s}=343-328.937=14.063

           v_{s}=\frac{14.063}{0.959}=14.66 \mathrm{m} / \mathrm{s}

Approximately 15 m/s is the speed of the car.

3 0
3 years ago
A 2kg toy car traveling at 2m/s strikes a second toy car at rest. The mass of the second toy car is 3. The two stock together an
Nutka1998 [239]
Mass of first car = Initial mass (Mi) = 2 kg
Initial velocity (Vi) = 2 m/s

Mass of both cars together = Final mass (Mf) = 2 + 3 kg = 5 kg
Final Velocity (Vf) = ?

Applying law of conservation of momentum,

Mi x Vi = Mf x Vf
2 x 2 = 5 x Vf
Vf = 4/5 = 0.8 m/s

7 0
3 years ago
Two teams are playing tug of war. The team on the right side is pulling with a force of 4332 N. The team on the left is pulling
OleMash [197]
As the greater force of tension (by 81N) is exerted by the team on the right the rope will move to the right.
6 0
3 years ago
Read 2 more answers
In the aerials competition in skiing, the competitors speed down a ramp that slopes sharply upward at the end. The sharp upward
11111nata11111 [884]

Answer:

u = 11.6 m/s

Explanation:

The end of a launch ramp is directed 63° above the horizontal. A skier attains a height of 10.9 m above the end of the ramp.

Maximum height, H = 10.9

Let v is the launch speed of the skier. The maximum height attained by the projectile is given by :

H=\dfrac{u^2\ sin^2\theta}{g}

10.9=\dfrac{u^2\ sin^2(63)}{9.8}

u = 11.6 m/s

So, the launch speed of the skier is 11.6 m/s. Hence, this is the required solution.

4 0
3 years ago
Suppose the battery in a clock wears out after moving thousand coulombs of charge through the clock at a rate of 0.5 Ma how long
Ksivusya [100]

Answer:

Hello your question is poorly written below is the complete question

Suppose the battery in a clock wears out after moving Ten thousand coulombs of charge through the clock at a rate of 0.5 Ma how long did the clock run on does battery and how many electrons per second slowed?

answer :

a) 231.48 days

b) n = 3.125 * 10^15

Explanation:

Battery moved 10,000 coulombs

current rate = 0.5 mA

<u>A) Determine how long the clock run on the battery. use the relation below</u>

q = i * t ----- ( 1 )

q = charge , i = current , t = time

10000 = 0.5 * 10^-3 * t

hence  t = 2 * 10^7 secs

hence the time = 231.48  days

<u>B) Determine how many electrons per second flowed </u>

q = n*e ------ ( 2 )

n = number of electrons

e = 1.6 * 10^-19

q = 0.5 * 10^-3 coulomb ( charge flowing per electron )

back to equation 2

n ( number of electrons ) = q / e = ( 0.5 * 10^-3 ) / ( 1.6 * 10^-19 )

hence : n = 3.125 * 10^15

8 0
3 years ago
Other questions:
  • The average salinity of sea water is<br> A. 3%<br> B. 3.5%<br> C. 2.5%<br> D. 2%
    9·2 answers
  • How does the force exerted by two magnets change as the magnets are moved farther apart?
    5·1 answer
  • The law of reflection states that light is reflected off a surface at the same angle that light hits the surface. The arrow on t
    13·2 answers
  • Mrs. Smith walks from her house 11.2 m to the grocer. Then she walks from the grocer 5.7 m to the pet store. Then she walks 32.7
    14·1 answer
  • In American football how many points.... look at the pic
    10·2 answers
  • A 400 µF capacitor is constructed out of two parallel plates of very large area which are separated by 1 mm. A battery is used t
    11·1 answer
  • The period T of a simple pendulum depends on the length L of the pendulum and the acceleration of gravity g (dimensions L/P). (a
    10·1 answer
  • What is Mass in sconce
    15·2 answers
  • A child and sled with a combined mass of 54.8
    11·1 answer
  • a projectile is launched horizontally from a height of 65 meters with an initial horizontal speed of 35 meters pre second. what
    10·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!